16. USING A DIRECT DRIVE MOTOR 
16 -  1 
 
16. USING A DIRECT DRIVE MOTOR 
CAUTION
 
 
When using the direct drive motor, read "Direct Drive Motor Instruction Manual". 
 
 
POINT 
 
The direct drive servo system is available for the servo amplifiers of which 
software version is A5 or later. 
 
 
16.1 Functions and configuration 
16.1.1 Summary 
The fields of semiconductor/LCD manufacturing systems, mounters, and others have strong demands for 
high accuracy and efficiency. Therefore, the number of systems using a direct drive motor for a drive axis 
has been increasing. The direct drive servo system includes the following features. 
 
(1) Performance 
(a)  The direct drive servo system ensures the high-rigidity and the high-torque. A high-resolution 
encoder enables the high-accuracy control. 
 
(b)  The high-resolution encoder contributes to the high-accuracy indexing. 
 
(c)  Since reducer is no longer required, no backlash occurs. In addition, the settling time is reduced, and 
the high-frequency operation is enabled. 
 
(d)  Since reducer is no longer required, the motor does not deteriorate with time by reducer. 
 
(2) Mechanism 
(a)  The motor's low profile design contributes to compact moving part of the machine and a low center 
of gravity for enhanced equipment stability. 
 
(b)  The motor has an inner rotor with hollow shaft which enables cables and pipes to be passed 
through. 
 
(c)  Lubrication and the maintenance due to abrasion are not required. 
 
The following shows the differences between the direct drive motor and the rotary servo motor. 
 
Differences 
Category Item 
Direct drive motor  Rotary servo motor 
Remarks 
Motor pole 
adjustment 
Magnetic pole detection  Required  Not required 
(default setting) 
Automatically executed at the first 
servo-on after the power is turned 
on. 
For the absolute position detection 
system, [Pr. PL01] can disable the 
magnetic pole detection. (Refer to 
(2) (b) of 16.3.3.) 
Absolute position 
detection system 
Absolute position encoder 
battery 
Required Required 
  Absolute position storage 
unit 
(MR-BTAS01) 
Required Not required